Removable Insulation Blankets – from A to Z
At first glance, making up a removable insulation blanket
seems somewhat simple – take some insulation, put some
mesh on one side, a cover on the other, sew them
together, add some rivets so that you can fasten it, and
presto!
Of course, we know that in fact it is not quite so simple.
Aside from the design aspect - that is ensuring that the
insulation blanket fits the part properly, wrapping snugly
around the part, and taking into account whatever
brackets, screws, and other protrusions might be present
- there is the aspect of choosing the appropriate materials
with which to manufacture the blanket.
“When it comes to selecting the material makeup of an insulation blanket, there
are numerous combinations of materials that are available”, notes Brett Herman,
Firwin’s vice-president of Sales & Engineering.
“While we have a standard material makeup that we default to for ‘ordinary’
insulation blanket applications, we manufacture a wide range of material
combinations on a regular basis”, said Brett. “A simple glance at our production
line at any one time would show blankets of all shapes, sizes, and materials
waiting to be assembled”, added Brett.
Removable Insulation Blanket Construction
As most of us know, a removable insulation blanket can be divided into 3 main
components:
• An outer protective cover, also known as the “cold face”, designed to shield
and protect the insulation from the environment in which it finds itself.
• The insulation mat itself, typically 1” thick fiberglass, which provides the
actual heat containment. Thickness varies from ½” to up to 4”, depending
on the amount of heat reduction the application requires.
• The inner liner, also known as the “hot face”, which helps to keep the
insulation mat in place, and can also act as a barrier, protecting the
insulation mat from fluid seepage.
Aside from these 3 components, there is the fastening system used to secure the
insulation blankets in place.
All of these aforementioned components can vary according the application in
question and the end user requirements. Some of the factors that the Firwin
design team takes into account when deciding on the material makeup of an
insulation blanket include:
• Maximum temperature range of the application in question.
• Location (i.e. indoors vs. outdoors).
• Exposure to elements (i.e. water, chemicals, debris, etc.)
• Ambient temperature
• Safety requirements (i.e. underground mining, marine, UL, etc.)
• Desired outer surface “touch temperature”
• Space limitations.
• Desired heat retention within the system (i.e. desired exhaust temperature)
• Regulatory requirements (i.e. Marine)
• Frequency of insulation removal
• Aesthetic requirements (i.e. look of blanket, color matching, etc.).
“Because of all the variables, it is important for us to know under what
circumstances the blankets will be used, and what objectives the end-user is
trying to achieve with the insulation, in addition to any constraints and design
specifications”, said Brett.
Materials Used in Removable Insulation Blanket Construction
As an educational resource to our customers, Firwin has put together the
following table (beginning on the next page), which outlines the more common
options available when constructing an insulation blanket. Note that while this
table is quite comprehensive, it is not exhaustive, there being other insulation and
cover materials available that are used in highly specialized applications. Please
be sure to consult with a Firwin representative before finalizing any material
choice.
Materials Used in Removable Insulation
Blanket Construction
Usage
Temperature
Range
Fluid
Barrier
Relative
Cost *
When Used
Special Properties
Silicone Impregnated Fiberglass Outer Cover; Inner Liner ‐67°F (‐55°C) to 500°F (260°C) Yes $$ Typical outer cover used in most standard insulation blanket applications. Also used as inner liner for applications < 500°F (260°C) where a fluid barrier or insulation fiber containment is desired. Flexible; flame retardant; water and oil resistant; mold resistant; chemical resistant. Typically grey or red, but other colors also available. Teflon Coated Fiberglass Outer Cover; Inner Liner ‐50°F (‐45.5°C) to 550°F (287°C) Yes $$ Used interchangeably with Silicone. Used in place of Silicone in Paint, Food, and other chemical applications due to broader chemical resistance. Flexible; flame retardant; water and oil resistant; mold resistant. Broad spectrum chemical resistance. Typically grey or red, but other colors also available. Aluminized Fiberglass Outer Cover ‐20°F (‐28°C) to 450°F (230°C) Yes $$$ Used in place of silicone / Teflon when one wishes to shield components from nearby heat source (i.e. insulate the "cold" component and reflect heat away, rather than insulate the hot component to retain heat). Also used for aesthetic reasons. Aluminized high reflective radiant barrier. Flame resistant, shows resistance to water and oils, mold resistant. Due to construction even when the aluminum coating breaks down (450°F/230°C), the fiberglass substrate maintains it's integrity up to 1000°F [538°C]. PVC Outer Cover; Inner Liner ‐40°F (‐40°C) to 180°F (82°C) Yes $ More economical alternative to Silicone and Teflon where high temperature rating is not required. Water and oil resistant; mold resistant, UV resistant ( ) This (Heavy Duty) silicone impregnated fiberglass fabric Similar characteristics to silicone Impregnated glass fabric.
Outer and Inner Covers
* Costing is not to scale, and is for comparative purposes only. This document is the property of Firwin Corp. Any unauthorized use is prohibited. Heavy Duty Silicone Outer Cover ‐67°F (‐55°C) to 500°F (260°C) Yes $$$ is often used in more severe outdoor applications, and in larger size applications where increased strength and resistance to wear and tear is needed. Provides superior resistance to abrasion, flexing, tear and puncture. Flame retardant; water and oil resistant; mold resistant. Fiberglass HT Outer Cover; Inner Liner ‐20°F (‐28°C) to 1300°F (700°C) No $$ A non‐coated fabric used both as an outer cover and inner liner in high temp exposure conditions(>500°F / 260°C) where Silicone and Teflon fabrics are unsuitable. Excellent resistance to high temperatures; mold resistant. Typically in blue or beige color. Good for containing insulation fibers. Silica Outer Cover; Inner Liner ‐20°F (‐28°C) to 1,800°F (982°C) NO $$$$ A non‐coated fabric used both as an outer cover and inner liner in extreme high temp exposure conditions(>1300°F / 982°C) where silicone and Teflon fabrics are unsuitable. Fireproof; Excellent Insulating Properties; mold resistant. Good for containing insulation fibers. Stainless Steel Laminated Fiberglass Outer Cover ‐20°F (‐28°C) to 500°F (260°C) Yes $$$$$$$$$ Used in place of coated fabrics (such as silicone and Teflon) where a high level of oil , chemical and fire resistance is required. Used together with a mesh outer cover for applications where strong puncture and tear resistance are needed. Unlike Aluminized Fiberglass where coating breaks down at high temperatures, laminated foil retains its integrity and can continue to act as a fluid barrier. Excellent puncture and tear resistance. Flame retardant; water and oil resistant; mold resistant. * Costing is not to scale, and is for comparative purposes only. This document is the property of Firwin Corp. Any unauthorized use is prohibited.Materials Used in Removable Insulation
Blanket Construction
Inner Covers
Usage
Temperature
Range
Fluid
Barrier
Relative
Cost *
When Used
Special Properties
Stainless Steel Mesh 304 Inner Liner 1200°F (649°C) No $$ Typical inner liner used in most standard insulation blanket applications > 500°F (260°C), where limited fiber containment is required. Also used as a reinforcement for outer covers where rocks , debris and damage resistance is needed. Stainless Steel Mesh 309 Inner Liner 1,800°F (982°C) No $$$ Used in place of stainless steel 304 for temperatures between 1200°F to 1800°F. Stainless Steel
Mesh Inconnel Inner Liner 2300°F (1260°C) No $$$$$$$$$ For extremely high temperature applications > 1800°F. Stainless Steel
Mesh 316 Inner Liner 1,600°F (871°C) No $$ș For marine environments Good resistance to sea water. Stainless Steel Foil with Mesh Cover Inner Liner 1200°F (649°C) Yes $$$ Used primarily in high temperature (> 500°F (260°C)) applications where a fluid barrier to insulation is desired. Exhibits high strength at elevated temperatures. Flame proof; water and oil resistant; mold resistant.
Insulation
Insulation
Material
Temperature Limit
Relative
Cost *
When Used
Properties
* Costing is not to scale, and is for comparative purposes only. This document is the property of Firwin Corp. Any unauthorized use is prohibited. FW1200 Fiberglass 1200°F (649°C) $ Typical insulation used in most standard insulation blanket applications with temperatures < 1200°F (649°C). Odorless, does not contribute to metal corrosion, and resists decay, mold, and vermin. Excellent sound absorption properties FW PLUS CMS Wool 2192°F (1200°C) $$ Enhanced thermal properties, ideal for very high temperature (> 1200°F (649°C)) applications, or for lower temperature applications where superior insulation value is required. Firwin Plus offers the equivalent thermal properties as ceramic insulation, without the health concerns the accompany ceramic insulation. Odorless, does not contribute to metal corrosion, and resists decay, mold, and vermin. Excellent sound absorption properties. MW1200 Mineral Wool 1200°F (649°C) $ș Ideal for applications where moisture is an issue. Water repellent, fire resistant and sound absorbent. Also has good vibration absorption. Low moisture absorption; Fire resistant; Excellent thermal resistance; Does not rot or sustain vermin; Does not promote growth of fungi or mildew. Good sound and vibration absorption. AHQ9233 Aerogel 1100 °F (600°C) $$$$$$$$ Superior insulation material to both fiberglass and CMS Wool. Ideal for limited clearance applications or where blanket weight is a concern. Due to it’s unique thermal conductivity qualities ½” thick will have similar insulation properties to 1 .5” of fiberglass insulation. * Costing is not to scale, and is for comparative purposes only. This document is the property of Firwin Corp. Any unauthorized use is prohibited.
